2016 Franklin Medal and prize of the Institute of Physics

Professor Raymond E. Goldstein, University of Cambridge and Churchill College Cambridge, for revealing the physical basis for fluid motion in and around active cells and its importance for the evolution of multicellularity, cell differentiation, and the synchronicity of eukaryotic flagella.

Professor Raymond Goldstein’s biological physics laboratory at the University of Cambridge is perhaps the most productive in the world.

Goldstein’s research concerns the interaction between active cells and their fluid environment. His observations of random coherent motions in concentrated suspensions of swimming bacteria have motivated many research groups to try to model them. The observations show the way in which complex behaviour at the population level can emerge from the relatively simple dynamics of individual cells. The large-scale suspension can be modelled as a continuum or as a collection of individuals obeying certain rules. Goldstein seeks to understand those rules.

He investigates the details of cellular phenomena, including the synchronisation of the two flagella of Chlamydomonas reinhardtii; how the location of the photoreceptor in Chlamydomonas determines its phototactic response; and measurement of detailed flow patterns around individual free-swimming algae and bacteria, requiring new, miniaturised imaging and measurement techniques.

Perhaps his most influential contributions are his studies of Volvox – colonies of green algae of different sizes. He showed that the transition, from irregular collections of identical cells to spherical colonies with internal germ cells and external somatic cells driving flow, occurs at exactly the colony size at which pure diffusion, unenhanced by advection with the external flow, becomes inadequate for nutrient supply – suggesting a purely physical basis for the evolution of multicellularity and cell differentiation.

Goldstein has been a fellow of the IOP since 2009 and was made a fellow of the Royal Society in 2013. He was recognised with the Senior Investigator Award from the Wellcome Trust for 2012–17 and an Established Career Fellowship from the EPSRC for 2015–20. In 2011 Goldstein won the Cambridge Philosophical Society’s William Hopkins Prize and in 2012 shared the Ig Nobel Prize in Physics “for calculating the balance of forces that shape and move the hair in a human ponytail”.